N°6934 - Symfony 6.4 - upgrade Symfony bundles to 6.4 (#580)

* Update Symfony lib to version ~6.4.0
* Update code missing return type
* Add an iTop general configuration entry to store application secret (Symfony mandatory parameter)
* Use dependency injection in ExceptionListener & UserProvider classes

lib/symfony/http-foundation/Session/SessionBagInterface.php

@@ -20,27 +20,25 @@ interface SessionBagInterface
 {
     /**
      * Gets this bag's name.
-     *
-     * @return string
      */
-    public function getName();
+    public function getName(): string;
 
     /**
      * Initializes the Bag.
+     *
+     * @return void
      */
     public function initialize(array &$array);
 
     /**
      * Gets the storage key for this bag.
-     *
-     * @return string
      */
-    public function getStorageKey();
+    public function getStorageKey(): string;
 
     /**
      * Clears out data from bag.
      *
      * @return mixed Whatever data was contained
      */
-    public function clear();
+    public function clear(): mixed;
 }